1. Field of the Invention
The present invention relates to an incoming call ringing method for a mobile terminal device, such as a portable telephone or PHS.
2. Description of the Related Art
In mobile communication with portable telephones, a user normally carries around a mobile terminal device in power ON mode and can make and receive a call anytime. Depending on the location or situation where a user is present, however, there may be case where generating a ringing tone would bother people in the adjacent area.
Recent mobile terminal devices are equipped with a reception mode called a manner mode. The manner mode is a reception mode that is used in case where generation of a ringing tone would bother people, such as in a movie theater or a train, or during a meeting, and does not generate a ringing tone at the time of receiving a call. In many cases, a user is informed of an incoming call by a vibrator instead of generating a ringing tone in manner mode.
Some mobile terminal devices generate a key-operation acknowledge tone at the time of making a call and at the time of sending and receiving e-mail. With the manner mode set, however, such a key-operation acknowledge tone is not generated in most cases.
Normally, the manner mode is set manually by a key operation by a user. In cases where the manner mode should be set, however, a user may forget the setting, or a user may forget to cancel the manner mode. Therefore, a ringing tone may be generated at a quiet place or an incoming call may not be noticed because of generation of no ringing tone. To overcome them, there are methods contrived that automatically set and cancel the manner mode.
One conventional method of automatically setting and canceling the manner mode is to store base station IDs for setting and canceling the manner mode in a mobile terminal device. According to the method, a mobile terminal device, which has stored base station IDs for setting and canceling, goes into the manner mode automatically when entering an area of a base station with the appropriate base station ID for setting the manner mode. Once the mobile terminal device enters an area of a base station with the base station ID for cancellation of the manner mode, it automatically goes to the normal reception mode when it leaves the area.
Another method of automatically setting and canceling the manner mode is to measure surrounding noise and automatically adjust the volume or timbre of a ringing tone according to the measured value.
The method of automatically setting and canceling the manner mode based on a base station ID can enable setting and cancellation only base station by base station and is effective for a PHS for which an area covered by a single base station is narrow. In a PDC type portable telephone system, in which an area covered by a base station is wide, it is difficult to enable the setting and cancellation of the manner mode.
The method of automatically adjusting the volume or timbre of a ringing tone according to the measured value of surrounding noise automatically sets and cancels the manner mode based on the volume, regardless of the surrounding situation. Therefore, there may be a case where the manner mode is set when the manner mode is not actually needed, or a case where the manner mode is not set when the manner mode should be set.